Probe sheath

ABSTRACT

The present invention relates to a protective sheath (cover) for a probe for therapeutic or diagnostic use, in particular an aseptic disposable sheath aiming to protect the probe from body fluids and to protect contamination, and the patient and nursing personnel from the transmission of pathogenic microorganisms.

AREA OF THE INVENTION

The present invention relates to a protective sheath (cover) for a probefor therapeutic or diagnostic use, in particular an aseptic disposablesheath aiming to protect the probe from body fluids and to protectcontamination, and the patient and nursing personnel from thetransmission of pathogenic mircoorganisms.

BACKGROUND OF THE INVENTION

In medical care various types of probes for diagnostic or therapeuticpurposes are used. For instance, probes intended for oral insertion inbronchoscopy, for rectal insertion for examination of the colon or forvaginal insertion for examination of the uterus. These probes comprisetransmitters for various types of radiation, for instance, ultrasound ormicro waves.

Probes are intended for long term use and examination of a large numberof patients. In order to reduce the time consumed in preparing a usedprobe for the next examination, it is known to provide the probe with aremovable cover of a polymer or similar material that can be disposedupon use. The sheath is designed in a way as to cover the parts of theprobe coming into contact with body fluids and tissues. For instance,the sheath can have a form similar to a condom, i.e., in principle, theform of a finger with an opening at its base for insertion of the probe.`Having the form of a finger` signifies tubular covers of various lengthhaving an insertion opening in their one end and a more or less bluntopposite end (top end) in the direction of which the cover may taper.This prevents contamination of the probe proper and transmission ofcontamination to the next patient or nursing personnel. A change ofcover suffices for preparing the probe for the next use. To make theprobe function properly, it is essential for the sheath covering theprobe to adopt the form or the latter thus to make as much contact withthe probe as possible.

The known protective sheaths can however be improved in regard of theirsimplicity and safety in use, that is, the ease with which they may bemounted on the probe and their contact with the probe.

DESCRIPTION OF THE INVENTION

The present invention relates to a protective sheath of theaforementioned kind which has improved properties in regard to themounting and/or abutment, and thus function.

According to the invention, there is disclosed a substantially fingerformed probe cover of the aforementioned kind provided mounted on aporous support and comprising a flat lower cover portion abuttingagainst the support and being wholly or partially fixed at its borderzone to the support in a way so as to enable it to be peeled off, andhaving a flat upper cover portion abutting against the lower coverportion and being congruent with it except at the insertion area, thelower cover portion at its insertion area being not covered by the uppercover portion and being fixed to the upper cover portion at its borderzone congruent in form.

It is preferred for the protective sheath to have, at its top end, achamber which can be opened from the base end side and which is filledwith a liquid or gelatinous contact means, said chamber being formed bya transverse connection of the upper and lower cover portions, saidconnection being executed for being opened (broken) upon insertion of aprobe into the sheath. Preferably the contact means is a liquid or a gelwith appropriate optical and/or acoustical properties.

It is furthermore preferred for the cover thickness to be from 00.1mm-0.1 mm, in particular from 0.02 to 0.05 mm.

It is also important for the protective sheath to have appropriategliding properties in regard of its inside (the side facing the probe)and of its outside (the side facing the body). It is also preferred thatone or both sides of the cover are treated with lubricating means; forinstance, it is appropriate to silanize the outside or to cover it witha thin layer of polyurethane swellable in water, or with a similarcovering. For the inside of the sheath simpler dry gliding means canalso be used, such as talcum. Various known sterilization techniques canbe used, such as radiation sterilization or ethylene oxidesterilization.

The abutment of the sheath against the probe can be improved by makingthe cover elastic and by preferably also providing it with a certainamount of non-elastic extendability. Suitable materials for such coversare certain types of polymers; a second choices are latex and syntheticrubber.

Further advantages of the invention will become apparent from thefollowing detailed description of two preferred embodiments and adrawing joined to the description, of which

FIG. 1 shows a top view of a probe cover fixed to a support, and

FIG. 2 shows the same probe cover in section B--B (FIG. 1), thethickness of the layers being exaggerated for reason of clarity.

The first preferred embodiment of the invention relates to a protectiveprobe cover or sheath of EMA copolymer (ethylene/polyacrylic acid),quality NCPE 540 Optene, thickness 0.025 mm.

In FIG. 1 this sheath is shown mounted on a support of thin paper 4having a raw upper surface. In FIG. 1 the upper half 2 of the sheathcovers the lower half except for a portion 1a at the sheath base. Theedges of halves 1 and 2 coinciding in the top view are connected bywelding in a circumferential border zone 3, except for the free edgesection 12 of upper portion 2 being not congruent in form with thecorresponding section 11 of lower portion 1. The connection of halves 1and 2 in border zone 3 at 8 by welding (FIG. 2) is carried out withlower half 1 resting on support 4, whereby a weak welding connection (at5; FIG. 2) of border zone 3 of sheath 1,2 to support 4 is also obtained.

In FIG. 2 the protective sheath is shown in section along line B--B(FIG. 1); along this line the combination of sheath and support isfolded for storage, sheath 1,2 thus resting in a cover 4 of paper. Forthe sake of clarity the thickness of the polymer and paper layers hasbeen much exaggerated. Loosely abutting portions are indicated by asmall interstice, the first interstice being located between the upper 1and the lower 2 polymer layer, and the interstice 14 between the lastmentioned layer 1 and support 4. Sheath 1, 2 is fixed at support 4 onlyat the periphery (at 5) of border zone 3.

The cover or sheath is mounted on the probe by moving the free probe end(insertion end) in the direction of the freely accessible portion 1a ofthe lower half and then in direction of edge 12, whereat the halves ofsupport 4 are folded by the operator's curved palm supporting 4 at itsback side, thus displacing the opposite border zones 3 towards eachother and tearing apart and enlarging the insertion opening at edge 12.Thereafter the probe is moved forward until it abuts against thecorresponding end of cover 1,2. Upon use the cover can be easily drawnoff by gripping flap 1a and moving it in the direction of the probeinsertion end.

In certain applications it is essential to avoid the formation of airpockets between the probe and the cover while the cover is mounted onthe probe. As a preventive measure a contact liquid or gel can beintroduced into opening 12 prior to mounting. To avoid losses of liquidor gel these materials however can be advantageously disposed at thelower cover end section 7 in a chamber 13 formed by transversepartitioning of the cover at 9 by welding (heat or ultrasound). Thiswelding connection is however, not made as permanent as weldingconnection 8 but rather in a way that it is easily broken upon cover 8expanding during probe insertion.

In the second preferred embodiment executed in a similar manner, cover1,2 can be open at the insertion end to provide for manipulation orinspection of tissue or similar elements by means disposed at said end.For instance, optical elements in combination with optically conductingfibres, gripping instruments of various kinds for sampling or operatingpurposes, cannulae, etc. all can be used. In this embodiment, the mainpart of the instrument is thus protected from contamination except for asmall area at its tip. Such an opening is indicated in FIG. 1 by hatchedsection line 14 delimitating the opening. This embodiment thus lacks thecap 15. It is also possible to reinforce the material at the borderzones of the front opening (at 16) to improve abutment reproducibilityin the longitudinal direction of the probe cover 1,2. It is alsopossible to provide a front opening which initially is closed by a sealor a welding connection at 14 which can be broken, that is, a thinbridge of material which is broken during probe insertion or, possibly,by a means which can be telescoped from the probe tip, such as a pair ofgripping tongs. In the last instance the probe is inserted into thepatient fully protected, and the seal is only broken upon the probehaving reached the desired position in the patient. The chamber formedby the two breakable seals 6, at 14, and the sheath portions locatedbetween them can be partially filled in a way as disclosed in connectionwith chamber 7.

I claim:
 1. A protective sheath comprising:a top end; a base endincluding an insertion opening for a probe; said sheath being mounted ona support; a flat lower cover portion abutting against the support andbeing wholly or partially fixed at its edge zone to the support in a wayso that the lower cover portion is detachably mounted to said support; aflat upper cover portion abutting loosely against said lower coverportion and being congruent in form with said lower cover portion exceptat the insertion opening, said lower cover portion at the insertionopening not being covered by the upper cover portion thereby forming afree flap, said lower cover portion being fixed to the upper coverportion at its border zone a chamber disposed at the top end of thesheath, the chamber being accessible from the base end side, the chamberbeing filled with a liquid or gelatinous contact material, the chamberbeing formed by a transverse connection of the upper and the lower coverportions, the transverse connection being formed so that it is openedupon insertion of a probe into the sheath.
 2. The protective sheathaccording to claim 1, wherein a resistance of the transverse connectionagainst penetration is less than of the connection between the upper andlower cover portions in the border zone.
 3. The protective sheathaccording to claim 1, wherein the contact material is a sterile gel. 4.The protective sheath according to claim 1, wherein the sheath has athickness which is from 0.01 mm to 0.3 mm.
 5. The protective sheathaccording to claim 1, wherein said sheath is treated with a lubricatingmeans on at least one side.
 6. The protective sheath according to claim1, wherein said sheath is formed in a permanently extendable and elasticcopolymer.
 7. The protective sheath according to claim 1, wherein saidsupport is comprised of a paper having a rough upper surface.
 8. Theprotective sheath according to claim 1, wherein said sheath has anopening or a breakable seal at its top end.
 9. The protective sheathaccording to claim 1, wherein a wall zone delimitating the insertionarea is reinforced.
 10. The protective sheath as claimed in claim 4,wherein said sheath has a thickness which is between 0.01 and 0.05 mm.11. The protective sheath as claimed in claim 6, wherein said sheath isformed by an ethylene/acrylic copolymer.
 12. A protective sheathcomprising:a top end; a base end continuous with said top end and havingan opening which is effective to receive a probe; a chamber disposed insaid top end, said chamber being defined by a cap of said top end, sidesof said top end, and a seal disposed between said chamber and said baseend.
 13. The protective sheath as claimed in claim 12, furthercomprising:an upper cover portion; a lower cover portion fixed to saidupper cover portion; a support detachably mounted to said lower coverportion.
 14. The protective sheath as claimed in claim 13, wherein saidupper cover portion covers all of said lower cover portion except for afree edge section.
 15. The protective sheath as claimed in claim 12,wherein said chamber contains a liquid disposed therein.
 16. Theprotective sheath as claimed in claim 12, wherein said cap comprises abreakable seal.
 17. The protective sheath as claimed in claim 12,wherein said seal is broken upon complete insertion of said probe.
 18. Amethod of inserting a probe into a probe sheath, said methodcomprising:inserting said probe into an opening of said probe sheath;breaking a seal disposed within said probe sheath using said probe; andinserting said probe further in to said probe sheath.
 19. The method asclaimed in claim 18, wherein said breaking introduces a liquid, storedin a chamber of said probe sheath, on to said probe.
 20. The method asclaimed in claim 18, further comprising detaching said probe and saidprobe sheath from a support detachably connected to said probe sheath.21. The method as claimed in claim 18, further comprising inserting saidprobe further through said probe sheath thereby breaking off a cap ofsaid probe sheath.